session_start seems to be very slow (but only sometimes)

Question

For some odd reason, just today our server decided to be very slow during the starting of sessions. For every session_start, the server either times out after 30 seconds, or

Answer 1

I had the same problem: suddenly the server took 30 seconds to execute a request. I noticed it was because of session_start(). The first request was fast, but each next request took some 30 sec to be executed. I found that the session file in c:\wamp\tmp was locked by the first request for some 30 sec. During this time the second request was waiting for the file to be unlocked. I found out it had something to do with rewrite_mod and .htaccess. I disabled rewrite_mod and commented out every line in .htaccess and it works again like a charm. I don't know why this happend because I don't remember change any settings or conf on wamp.